sym·​bi·​ont | \ ˈsim-bē-ˌänt How to pronounce symbiont (audio) \

Definition of symbiont

: an organism living in symbiosis especially : the smaller member of a symbiotic pair

Examples of symbiont in a Sentence

Recent Examples on the Web Butler suggests that the Ina-symbiont relationship might be no worse than the forms of dependency that humans already take for granted. Julian Lucas, The New Yorker, "How Octavia E. Butler Reimagines Sex and Survival," 8 Mar. 2021 One symbiont found in Costa Rica was hiding in plain sight: a beetle that clamps its mandibles around the ant’s middle and rides along, looking like a double-vision version of the ant’s backside. National Geographic, "Beetle behinds, flamingo friendships, and other wonders," 11 Aug. 2020 Still, a team led by CSIRO’s Patrick Buerger wondered if there might be a way to help, at least to some extent, by raising heat-tolerant strains of the corals’ symbionts. Scott K. Johnson, Ars Technica, "Could lab-evolved algae help save some corals from bleaching?," 14 May 2020 Certain algae species serve as symbionts for Cassiopea jellyfish, providing the animals with nutrients harvested from sunlight by way of photosynthesis. Cheryl Ames, National Geographic, "THE BEST OF NATIONAL GEOGRAPHIC DELIVERED TO YOUR INBOX," 13 Feb. 2020 In other sap-sucking insects, symbionts serve additional functions, Moran and her colleagues discovered. Elizabeth Pennisi, Science | AAAS, "A love of insects and their microbial partners helped this biologist reveal secrets of symbiosis," 14 Nov. 2019 Skillings and other critics argue that there just isn’t enough evidence of vertical transmission of symbionts to allow for the holobiont to be a coherent evolutionary individual. Quanta Magazine, "Should Evolution Treat Our Microbes as Part of Us?," 20 Nov. 2018 This jet forces out oxygen that accumulates in the middle of the polyp (thanks to its resident symbionts, photosynthetic algae called zooxanthellae). Scientific American, "Nanomachines, Jellyfish Hugs and Hurricane Dorian From Space: The Week's Best Science GIFs," 30 Aug. 2019 For decades, researchers have known that mitochondria are derived from bacteria that became internal symbionts of archaeal cells, but details of how that happened have been sketchy. Quanta Magazine, "Researchers Rethink the Ancestry of Complex Cells," 9 Apr. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'symbiont.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of symbiont

1887, in the meaning defined above

History and Etymology for symbiont

borrowed from German Symbiont, probably altered (after Greek ont-, stem of ṓn, present participle of eînai "to be") from symbiount-, stem of symbiôn, present participle of symbioûn "to live together" — more at symbiosis

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Time Traveler for symbiont

Time Traveler

The first known use of symbiont was in 1887

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Statistics for symbiont

Last Updated

16 Mar 2021

Cite this Entry

“Symbiont.” Dictionary, Merriam-Webster, Accessed 6 May. 2021.

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More Definitions for symbiont


sym·​bi·​ont | \ ˈsim-ˌbī-ˌänt How to pronounce symbiont (audio) , -bē- How to pronounce symbiont (audio) \

Medical Definition of symbiont

: an organism living in symbiosis especially : the smaller member of a symbiotic pair

called also symbiote

Other Words from symbiont

symbiontic \ ˌsim-​ˌbī-​ˈänt-​ik, -​bē-​ How to pronounce symbiont (audio) \ adjective

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